1. Field of the Invention
This invention relates to a one-piece adjusting sleeve and more particularly for an adjusting sleeve to adjust the camber and castor or pneumatic trail of a steerable wheel assembly.
2. Description of the Prior Art
Sleeves with an eccentrically displaced hole therethrough are used to adjust the camber and/or caster of a steerable wheel assembly. The sleeve has an outer surface rotatable with respect to its central axis and an eccentrally displaced aperture therethrough with its axis parallel to the central axis of the outer surface. A ball stud is inserted within the eccentric hole. Rotation of the sleeve adjusts the member which mounts the sleeve with respect to a member which mounts the ball joint which has the integral stud thereon. One such eccentric sleeve is disclosed in U.S. Pat. No. 4,026,578 issued to Mattson on May 31, 1977. The sleeve in the Mattson patent is used in a MacPherson strut assembly. Similar sleeves have also been known to be used in a steerable wheel assembly using a spindle with an upper and lower arm mounted by a ball joint to lower and upper control arms.
These eccentric holes within sleeves adequately adjust the camber and/or caster of a wheel assembly within a certain range. However, the range is limited due to the sleeves maximum diameter which in turn is limited due to the width of the spindle control arm to which it is mounted. In addition, the range of adjustment is limited due to the structure of the sleeve and its relation to the spindle and ball stud. In wheel assemblies that incorporate lower and upper control arms and a spindle mounted thereto through the use of ball joints, camber and castor adjustment changes the angle of the spindle due to rotation of the spindle about the center of the ball joint. Due to this angling, the ball stud which is adjustable must point in a direction away from the motion of the spindle which causes the spindle to move partially back from the desired direction of adjustment in order for the hole and ball stud to correctly fit together. The retrograde motion of the stud unduly limits the range of adjustment of a given diameter sleeve.